Catalysts are widely used in many industrial applications, such as pharmaceutical and fine chemicals manufacturing. A catalyst may be necessary for a reaction to occur or for the process to be economically viable. Many catalysts are expensive because they are made from precious metals, such as platinum or palladium, or because of the processing required to make a catalyst of a particular size, shape, or crystal phase. Because of the scale of industrial process and the expense of the catalysts it is desirable to be able to recover and reuse catalysts. Tradition methods of recovery have met limited success, however.
Furthermore, enzymes catalyze some industrially important reactions. The limited stability, high substrate specificity, and limited availability of sufficient quantities of some enzymes, however, have tended to limit their use. Thus, a need exists for small, stable, biomimetic catalysts that also could be recovered and reused.